An early exercise for newcomers to mindfulness is to mindful-y eat a strawberry (a raisin, grape or other small fruit is allowable if strawberries are out of season). Look at it, smell it, bite into it, feel its texture in your mouth, taste its juice, chew it, swallow it: be aware that you’re eating it (try not to be the one who swallows it straight away and has to get another one to do the exercise properly…).

Mindfulness, the argument goes, helps you to be more aware and accepting of your internal experiences and yourself. You get better at recognising anger or sadness as different from hunger, you pay more attention to what you are eating and when you are full. And it reduces stress, thus also decreasing the tendency to reach for the chocolate biscuits, so you’ll lose weight that way too. It sounds like a pretty convincing argument, and it’s made by many online purveyors of weight loss techniques.

But what evidence is there that it works? The authors of a recent systematic review in the Eating Behaviors journal have kindly done the legwork for us by reviewing all the existing studies of mindfulness-based techniques for binge eating, emotional eating and weight loss.

Methods

Design

The authors pre-registered their review online, and followed PRISMA recommendations. They searched appropriate databases using appropriate terms, and reviewed reference sections for articles they had missed.

Study selection

To be included, articles had to be original, published, include pre/post measures and an intervention, include mindfulness training in every session, and measure binge eating, emotional eating or weight loss. They were excluded if they included participants with anorexia or bulimia nervosa, those undergoing chemotherapy, case studies or those with a sample size of less than five.

Data extraction

Two authors independently evaluated selected studies for data extraction, including calculating within and between group Cohen’s d effect sizes. Information was then compared to check accuracy.

Risk of bias

Bias within studies was assessed, including whether outcomes were primary or secondary.

People with eating disorders have relatively few treatment options, so new possibilities are always worth investigating

Results

50 studies were identified as potentially relevant; only 14 met all the eligibility criteria; 11 were conducted in the USA. Length of interventions ranged from 6-16 weeks; age from 18-75; percentage of male participants from 10-37%, except in one study with 87.5% men. The majority used binge or emotional eating as a primary outcome measure, with recognised scales.

Only 7 studies had a control group of any sort. The number of participants in these studies ranged from 10-108. This summary includes only results where there was a control group for comparison, as comparing before and after without a control group is not meaningful. Results presented in the text and tables are contradictory as to which studies used binge eating and which used emotional eating as their outcomes. I have referred to the tables here, and scurried back to check the original references where possible.

Binge Eating

Was reduced in comparison to control group in 1 study (effect size of 1.10)

Was very slightly reduced in comparison to CBT in 1 study (effect size 0.31), and no different from CBT in another study

Emotional Eating

Was reduced in comparison to control in 2 studies (effect sizes 0.53 and 0.57) but not in a third

Weight

Did not change in relation to control in 3 studies

Weight loss was less than for CBT in one study

There was slightly less weight gain (sic) in comparison to controls in one study

Mindfulness is a promising intervention for many mental health conditions, but this review does not provide sufficient evidence to recommended it for treating or preventing binge eating

Comments

So can mindfulness work its magic on binging and emotional eating? The authors conclude that:

Mindfulness training may be an important contributor to positive changes in disordered eating.

I think this is an overstatement given the current literature. They acknowledge that the studies were small and that the outcomes used were different between studies, making comparison harder. They also acknowledge that, as with any review, it is likely that effects will be overstated, because negative or “null” results are less likely to be published. However, in this case, the authors found and then discarded 10 unpublished studies, which is a pity.

Mindfulness may do many things, and is queuing up to take its place with CBT as the panacea of mental illness, but I don’t think it can lay claim to binge eating yet.

As to our waist lines: the authors state that:

A standard Mindfulness-Based Stress Reduction program alone does not appear to invoke weight change.

I agree entirely. Chew your strawberries slowly ladies and gentleman, and savour each one as you go. It may add to your enjoyment, but I’m afraid there’s no evidence that by doing so you will lose weight.

This review finds that Mindfulness-Based Stress Reduction will not help you lose weight. Healthy eating and regular exercise remain the order of the day!

Helen Bould is currently a Wellcome Trust Doctoral Training Fellow at the Department of Psychiatry, University of Oxford. By background she is an Advanced Training Registrar in Child and Adolescent Psychiatry. Her research interests are in the epidemiology of and cognitive processes underlying body dissatisfaction and eating disorders. She is also more widely interested in how we understand and treat mental illness in children and adolescents. She completed her MA in Medical and Veterinary Sciences at University of Cambridge and her BMBCh at the University of Oxford. She is a member of the Royal College of Psychiatrists.